In light of the fact that fluorescent lighting provides up to 25% energy cost savings over incandescent bulbs, most office and warehouse environments are lit through the use of fluorescent lighting. Notwithstanding such savings, the power consumption of such lighting installations is significant because of their extensive coverage and prolonged use. Moreover, fluorescent lighting is not very amenable to flexible control, and can be difficult to dim and thus incapable of reducing power consumption during non-peak hours. Indeed, it is common practice to have designated fixtures that remain on at night after normal business hours (i.e., night lights) and all other room lights (i.e., the general lighting) have been turned off. The reduced number of lights that serve as night lights provide low level lighting for safety and security purposes. These designated night light fixtures therefore are on for twenty four hours a day, 365 days a year at full capacity. This not only wastes a tremendous amount of energy, it reduces the life of the ballasts and fluorescent bulbs and therefore increases the costs associated with providing lighting. Of possibly greatest concern, the discarded fluorescent bulbs necessarily contain mercury, which cannot be altogether eliminated from the bulbs. It is estimated that discarded fluorescent lamps release approximately 2 to 4 tons of mercury into the environment each year. (United States EPA Report on Fluorescent Lamp Recycling, February 2009, EPA530-R-09-001). Extending the life of fluorescent bulbs, even if just a portion of those that are used, would have the beneficial effect of reducing environmental mercury levels.
Fluorescent lights also have a relatively short lifetime and a high current draw as compared to some other types of lighting, and in particular in comparison with LEDs. Thus, retrofitting fluorescent lighting fixtures with LEDs or the like that provide night time light at a reduced power consumption using existing ballasts can help to relieve some of the above power and environmental problems by conserving energy (and the greenhouse gasses associated with generating that energy) and extending the life of the fluorescent bulbs without the significant cost of replacing all the current lighting fixtures present at a facility.
It would therefore be advantageous to provide a lighting system which overcomes one or more of the disadvantages or limitations of conventional fluorescent lighting systems by reducing power consumption and/or improving the life expectancy of the fluorescent bulbs and/or lighting ballast.